Monocoque composite structure

Abstract

The application provides a whole type reinforced composite vehicle body structure, which is characterized by the following: T-shaped longitudinal reinforcing members are arranged in the length direction of the vehicle body to load a vehicle head cover, a vehicle roof and a vehicle side wall plate; ring-shaped cap-shaped transverse reinforcing members are arranged in the width direction of the vehicle body; the longitudinal reinforcing members and the transverse reinforcing members are integrally formed with the outer wall plate skin through a co-curing / co-bonding process; the roof and the side wall plate are connected through longitudinal joints in the length direction of the vehicle body by using T-shaped longitudinal reinforcing members; the transverse reinforcing members are sleeved outside the transverse reinforcing members of the roof and the side wall plate and connected into an integral load-bearing frame by using cap-shaped transverse reinforcing members; the vehicle head cover and the vehicle body are fixedly connected in the ring-shaped connecting area; and the composite vehicle body and the aluminum alloy underframe are fixedly connected in the connecting area. The application improves the integrity of the vehicle body structure, integrally forms the vehicle body structure through the co-curing / co-bonding process, reduces the workload of subsequent assembly, improves the production efficiency of large parts, and reduces the manufacturing cost.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of rail vehicle manufacturing, and particularly relates to a whole type stiffened composite material vehicle body structure. BACKGROUND

[0002] Nowadays, high efficiency, light weight and environmental friendliness have become important development directions of high-speed trains. Therefore, the light weight and reliability of the vehicle body structure of high-speed trains are put forward with higher requirements.

[0003] Carbon fiber composite material is a new type of light weight and high performance structural material, and is widely used in the fields with high requirements for structural light weight such as aviation and aerospace. In recent years, the application of carbon fiber composite material in the field of rail vehicles has experienced a development process from secondary load-bearing structures such as interior wall panels, aprons and equipment cabins to primary load-bearing structures such as vehicle bodies and frames. At present, the composite material load-bearing vehicle body structure mostly adopts a sandwich structure formed by a foam or honeycomb core material and a carbon fiber skin, and the sandwich structure has more curing processes, a more complex forming process, more difficult processing of connecting structures and poor maintainability. Meanwhile, the traditional stiffened wall panel structure is only a unidirectional reinforced structure, and the transverse reinforcement is mostly secondary assembly, which has many parts and a complex assembly process, is not suitable for low-cost continuous production, and seriously restricts the application of composite materials and the development of light weight of high-speed trains. SUMMARY

[0004] The present application aims to provide a whole type stiffened composite material vehicle body structure, which ensures that the structure has high strength and stiffness characteristics in the longitudinal and transverse directions, greatly reduces the assembly work of the subsequent wall panel structure, improves the manufacturing and production efficiency, reduces the vehicle production cost, and effectively improves the reliability and use cost of the vehicle body main load-bearing structure in the whole life cycle of vehicle operation.

[0005] To achieve the above-mentioned purposes, the application provides a whole type reinforced composite material vehicle body structure, which is characterized by comprising a composite material bearing vehicle head cover, a composite material vehicle body top plate, a composite material vehicle body side wall plate, a vehicle body end wall and an aluminum alloy chassis; the bearing vehicle head cover, the vehicle body top plate and the vehicle body side wall plate are provided with T-shaped longitudinal reinforcing members in the length direction of the vehicle body and ring-shaped cap-shaped transverse reinforcing members in the width direction of the vehicle body; the longitudinal reinforcing members and the transverse reinforcing members are integrally formed with the outer wall plate skin through a co-curing process; the vehicle body top plate and the vehicle body side wall plate are longitudinally connected in the length direction of the vehicle body, and the longitudinal joints are connected by using T-shaped longitudinal reinforcing members; the cap-shaped transverse reinforcing members are sleeved outside the transverse reinforcing members of the vehicle body top plate and the vehicle body side wall plate and are connected into an integral bearing frame; in the bearing vehicle head cover and the vehicle body ring connection area, a reinforcing belt plate and a transversely arranged C-shaped ring connection reinforcing frame are fixedly connected, an avoiding opening is processed at the position through which the longitudinal reinforcing member of the bottom, and a Z-shaped connecting piece is arranged on the plane on one side of the T-shaped longitudinal reinforcing member of the vehicle body and the vehicle head cover and is fixed with the vehicle body; in the composite material vehicle body and the aluminum alloy chassis connection area, a full-length carbon fiber composite material connecting plate is used to fixedly connect the vehicle body side wall plate and the aluminum alloy chassis.

[0006] Further, the transverse reinforcing member is a cap-shaped foam sandwich composite material reinforcing member, and the height of the cap-shaped reinforcing member is 20-50 mm higher than the maximum height of the T-shaped reinforcing member section at the staggered position with the T-shaped longitudinal reinforcing member.

[0007] Further, the T-shaped reinforcing member opening is edge sealed and reinforced.

[0008] Further, it further comprises an opening reinforcing frame and a reinforcing corner piece, and the opening reinforcing frame is arranged at the opening area of the air conditioner port and the window port of the vehicle body top plate to reinforce the opening position, the opening reinforcing frame structure section can be L-shaped or C-shaped, the opening reinforcing frame is fixedly connected with the vehicle body top plate through a connecting reinforcing corner piece, and local reinforcing layers are used to locally reinforce the wall plate skin at the opening reinforcing frame connection area.

[0009] Further, it further comprises a side wall and chassis connection corner piece, which is a triangular reinforcing member with a shape matching the shape of the side wall and chassis corner, and the side wall and chassis connection corner piece connects the transverse reinforcing member of the vehicle body side wall plate and the aluminum alloy chassis.

[0010] Further, it further comprises an integral reinforcing door frame, a connecting plate and a connecting corner box, the integral reinforcing door frame is fixedly connected with the longitudinal reinforcing member of the vehicle body side wall plate through a Z-shaped connecting piece, the integral reinforcing door frame is fixedly connected with the transverse reinforcing member through a connecting plate, and the lower end of the integral reinforcing door frame is fixedly connected with the aluminum alloy chassis through a triangular connecting corner box.

[0011] Compared with the prior art, the application has the following advantages:

[0012] (1) The integral stiffened composite panel ensures the continuity of the stiffened panel in the longitudinal and transverse directions, improves the integrity of the structure compared to the traditional unidirectional stiffened panel structure, is integrally formed by co-bonding / co-curing, reduces the workload of subsequent assembly, improves the production efficiency of large parts, and reduces the manufacturing cost.

[0013] (2) The integral stiffened composite panel can fully exert the strong designability of composite materials. The application of topology optimization technology facilitates the reasonable layout and distribution of the reinforcing member. The application of size optimization technology and layer optimization technology facilitates the adjustment of the layer thickness and angle ratio of the skin. In the area with high structural load-bearing efficiency, the thickness of the skin and the proportion of unidirectional layers are increased. At the same time, compared with the traditional sandwich structure, the variable thickness design of the skin of the integral stiffened composite panel does not increase the additional technical difficulty of the design and production of the reinforcing member and the integral panel.

[0014] (3) In the straight section of the vehicle body, the longitudinal reinforcing rib and the Z-shaped connecting piece are designed in a modular manner and are formed by using the textile pultrusion process, realizing the continuous and automatic production of the composite parts and effectively improving the production efficiency of the reinforcing member.

[0015] (4) The transverse reinforcing member of the vehicle body adopts the form of a hat-shaped reinforcing rib supported by a foam core, which can be quickly formed into a transverse reinforcing member with curvature by using the semi-automatic or automatic preforming and preforming body formed by manual lamination + heat-separable membrane preforming or automatic tape laying + heat-separable membrane forming on a flat plate.

[0016] (5) Compared with the traditional sandwich structure, longitudinal and transverse connecting pieces can be used in the connection between the windows, doors, and parts to form a continuous and integral force transmission path, effectively improving the load-bearing capacity and connection reliability of the structure and reducing the weight of the vehicle body structure.

[0017] (6) Compared with the traditional sandwich structure, the integral stiffened composite panel has great advantages in the repairability of the part. When common damages such as impact and collision occur, the internal reinforcing plate can be used for quick reinforcement. Due to the good openness of the structure, the sealing treatment of the reinforcing structure and the main structure is more convenient, which can effectively avoid the problem of reduced water tightness caused by repair.

[0018] (7) The integral stiffened composite panel has more internal operating space, which is convenient for the arrangement of subsequent cold-proof materials and sound-absorbing materials. It has good adaptability to the change of subsequent interior structure and can be directly realized by relying on the longitudinal and transverse reinforcing members. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1The diagram of the division of the structure parts of the head of the high-speed train;

[0020] Figure 2 The structure diagram of the whole stiffened wall plate of the composite head cover;

[0021] Figure 3 The structure diagram of the whole stiffened wall plate of the composite roof;

[0022] Figure 4 The structure diagram of the whole stiffened wall plate of the composite side wall plate;

[0023] Figure 5 The structure diagram of the staggered position of the longitudinal and transverse stiffeners;

[0024] Figure 6 The positioning diagram of the longitudinal reinforcing member of the whole wall plate;

[0025] Figure 7 The pre-forming diagram of the heat diaphragm of the transverse stiffener;

[0026] Figure 8 The connection and reinforcing structure diagram of the opening position of the car body;

[0027] Figure 9 The longitudinal connection structure diagram of the roof and side wall plate;

[0028] Figure 10 The transverse connection structure diagram of the head cover and the car body part;

[0029] Figure 11 The detail structure diagram of the transverse connection structure;

[0030] Figure 12 The connection structure diagram of the side wall and the underframe;

[0031] Figure 13 The reinforcing structure diagram of the door frame;

[0032] Wherein: 1, the head cover; 2, the roof of the car body; 3, the side wall plate of the car body; 4, the end wall of the car body; 5, the aluminum alloy underframe; 11, the longitudinal reinforcing member; 12, the transverse reinforcing member; 13, the edge sealing reinforcing layer; 14, the opening reinforcing frame; 15, the wall plate skin; 16, the local reinforcing layer; 17, the transverse reinforcing member layer; 18, the foam support core material; 19, the whole reinforcing door frame; 20, the forming mold; 21, the flat plate mold; 30, the polytetrafluoroethylene pin; 31, the heat diaphragm plate; 40, the reinforcing corner piece; 50, the T-shaped longitudinal stiffener; 51, the cap-shaped transverse stiffener; 52, the reinforcing frame; 53, the reinforcing belt plate; 54, the Z-shaped connecting piece; 55, the connecting corner piece of the side wall and the underframe; 56, the connecting corner box; 57, the connecting plate. DETAILED DESCRIPTION

[0033] In order to better understand the purpose, structure and function of the present application, the whole body of the present application is described in further detail below.

[0034] The present application designs a whole body of the present application, which is a whole body of the present application. The arrangement of the reinforcing member is determined by topology optimization and size optimization. Through modular design, the structure form suitable for automatic / semi-automatic production is selected, the wall skin, reinforcing member and connecting piece are designed as the structure style which can be used for automatic fiber laying, automatic tape laying, hot diaphragm forming, pultrusion forming and die forming, and the manufacturing process of pre-impregnated material non-heat pressure tank co-curing / co-bonding is adopted to form the main load-bearing structure which meets the requirements of the structure / function of the vehicle body.

[0035] As shown in Figure 1 , according to the function and load-bearing characteristics of the vehicle body, the performance advantages of composite materials and metal materials are fully utilized, and the vehicle body is divided into a composite material load-bearing vehicle head cover 1, a composite material vehicle body top plate 2, a composite material vehicle body side wall plate 3, a vehicle body end wall 4 and an aluminum alloy chassis 5 and other components.

[0036] As shown in Figures 2-4 , the load-bearing vehicle head cover 1, the vehicle body top plate 2 and the vehicle body side wall plate 3 all adopt the whole body of the present application. T-shaped longitudinal reinforcing members 11 are arranged in the length direction of the vehicle body, and ring-shaped cap-shaped transverse reinforcing members 12 are arranged in the width direction of the vehicle body. The longitudinal reinforcing members 11 and the transverse reinforcing members 12 are integrally formed with the outer vehicle body skin by co-curing / co-bonding process, thereby reducing the mechanical connection between the reinforcing members and the skin, and ensuring the continuity of the structural strength / stiffness of the skin, longitudinal reinforcing members and transverse reinforcing members in all directions.

[0037] As shown in Figure 5 , the T-shaped longitudinal reinforcing member 11 is formed by pultrusion continuous forming process. The reinforcing rib section form is divided into regions according to the overall size optimization result and the load-bearing requirement of the reinforcing member, and is designed according to the general modularization. The transverse reinforcing member 12 is a cap-shaped foam sandwich composite material reinforcing rib. At the staggered position with the T-shaped longitudinal reinforcing member 11, the cap-shaped reinforcing rib is opened according to the T-shaped reinforcing rib, and the height of the cap-shaped reinforcing rib is 20-50mm higher than the maximum height of the T-shaped reinforcing rib section. The edge sealing reinforcing layer 13 is made at the opening of the T-shaped reinforcing rib to realize the continuity of the structural stiffness of the wall plate reinforcing rib in the longitudinal and transverse directions.

[0038] As shown in Figure 6As shown, the T-shaped longitudinal reinforcing member 11 needs to ensure sufficient positional accuracy during co-bonding forming, and a positioning reference hole with a diameter of Φ4mm-Φ6mm is reserved on the forming mold 20 (generally, the edge hole position is used as the reference hole during subsequent assembly). The positioning opening is machined in the corresponding position of the T-shaped longitudinal reinforcing member 11 after pultrusion. During the wall panel skin laying, the polytetrafluoroethylene pin 30 is placed in the positioning hole reserved on the forming mold 20, and then the wall panel skin 15 is laid. After the skin laying is completed, the prefabricated opening of the T-shaped longitudinal reinforcing member 11 is aligned with the polytetrafluoroethylene pin 30, the positioning of the T-shaped longitudinal reinforcing member 11 is completed, and the positional accuracy of the T-shaped longitudinal reinforcing member 11 is ensured.

[0039] As shown in Figure 7 The transverse reinforcing member adopts a cap-shaped structure with foam as the supporting core material. The core material is PMI foam or high-performance PET foam. The cross-sectional size is determined according to the size optimization results, and the cap-shaped supporting core material specifications are unified. This structure is beneficial to modularization and mass production. The transverse reinforcing member layer 17 is laid on the flat mold 21 using an automatic tape layering machine or manual layering. After the flat laying is completed, the flat layer is transferred to the hot diaphragm machine 31 to use the thermoforming process to bond the foam supporting core material 18, and the preparation of the cap-shaped preform is completed. After thermoforming, the cap-shaped preform is transferred to the wall panel laying tool and embedded in the T-shaped reinforcing rib to complete the laying preparation. After bagging and curing, the overall stiffened composite wall panel is obtained.

[0040] As shown in Figure 8 As shown in the drawings, an opening reinforcing frame 14 is used to reinforce the opening position in the air conditioning port, window and other opening areas of the vehicle body roof 2. The opening reinforcing frame is a carbon fiber composite material laminate structure. The structure section of the reinforcing frame can be L-shaped or C-shaped according to the connection and strength requirements. The pre-cured and formed opening reinforcing frame 14 is connected to the vehicle body roof 2 by connecting reinforcing corner pieces 40. The connecting reinforcing corner pieces are L-shaped carbon fiber composite material laminates. In the connecting area of the opening reinforcing frame 14, local reinforcement layers 16 are used to locally reinforce the wall panel skin 15 to improve the load-bearing capacity of the opening connecting area. According to the strength requirements of the connecting area, the connection method can be mechanical connection by fasteners or adhesive connection by structural adhesive. The opening reinforcing frame and the longitudinal and transverse reinforcing members of the wall panel form a direct force transmission path, ensuring the continuity of the in-plane stiffness and out-of-plane stiffness, and improving the overall load-bearing capacity of the structure.

[0041] As shown in Figure 9As shown, the longitudinal connection of the roof 2 and the side wall 3 in the vehicle length direction adopts the form of butt joint or lap joint, and the longitudinal joint is connected and reinforced by using the carbon fiber composite material T-shaped longitudinal reinforcing rib 50. The carbon fiber composite material cap-shaped transverse reinforcing rib 51 is sleeved outside the transverse reinforcing member 12 of the roof 2 and the side wall 3 of the vehicle body and is connected into an integral load-bearing frame. The longitudinal connection in the vehicle length direction is mechanically connected by using rivets or bolts, which ensures the reliability of the connection of the large components, and at the same time, the reinforcing members in the large components form a continuous force transmission path, which together forms a barrel-shaped integral load-bearing vehicle body, thereby improving the structural load-bearing efficiency. The lap joint form can effectively reduce the risk of water leakage in the vehicle body.

[0042] As shown in Figure 10 and Figure 11 , in the connection area of the load-bearing vehicle head cover 1 and the vehicle body, the enhanced belt plate 53 and the C-shaped ring connection reinforcing frame 52 are used for connection, wherein the enhanced belt plate 53 is a carbon fiber composite material laminate structure, and the C-shaped ring connection reinforcing frame 52 is a carbon fiber composite material C-shaped laminate structure. An avoidance opening is processed at the position of the longitudinal reinforcing rib passing through the bottom, and the gap between the edge of the avoidance opening and the upper end of the reinforcing rib should be not less than 20 mm. At the same time, the Z-shaped connecting piece 54 is used, which is arranged on one side of the T-shaped longitudinal reinforcing rib 11 of the vehicle body and the vehicle head cover and is mechanically connected to the vehicle body by using rivets or bolts. Finally, the vehicle head cover and the vehicle body form a longitudinal and transverse in-plane and out-of-plane stiffness continuous load-bearing structure, which improves the bending resistance and torsional resistance of the whole vehicle.

[0043] As shown in Figure 12 , in the connection area of the composite material vehicle body and the aluminum alloy chassis 5, the full-length carbon fiber composite material connecting plate 57 is used to mechanically connect the skin of the side wall plate of the vehicle body and the aluminum alloy chassis by using rivets or bolts, so as to ensure the longitudinal connection strength of the side wall plate of the vehicle body and the chassis. The carbon fiber composite material side wall and chassis connecting corner piece 55 is used to connect the transverse reinforcing member 12 of the side wall plate of the vehicle body and the aluminum alloy chassis, and is mechanically connected by using rivets or bolts. The shape of the side wall and chassis connecting corner piece 55 is a triangular reinforcing rib which is matched with the shape of the side wall and chassis corner, so as to ensure the transverse connection strength of the side wall plate of the vehicle body and the chassis.

[0044] As shown in Figure 13As shown, in the high stress area such as the door opening of the vehicle body, the pre-cured carbon fiber composite material is mechanically connected to the longitudinal reinforcing member 11 of the vehicle body side wall plate 3 through the carbon fiber composite material Z-shaped connecting piece 54, and the carbon fiber composite material is mechanically connected to the transverse reinforcing member 12 of the vehicle body side wall plate 3 through the carbon fiber composite material connecting plate 57, and the lower end of the carbon fiber composite material is mechanically connected to the aluminum alloy underframe 5 through the aluminum alloy bottom triangular connecting corner box 56. Finally, a continuous integral load-bearing structure is formed in the door opening area, and through the multi-component mechanical connection mode, the installation compensation and adjustment can be carried out to ensure the installation precision of the complex connecting mechanism such as the vehicle door, and the load-bearing capacity of the high stress area is improved.

Claims

1. A monolithic reinforced composite material vehicle body structure, characterized in that: The vehicle includes a composite material front hood (1), a composite material roof panel (2), a composite material side wall panel (3), a vehicle body end wall (4), and an aluminum alloy underframe (5). The front hood (1), roof panel (2), and side wall panel (3) are all equipped with T-shaped longitudinal reinforcement members (11) in the length direction of the vehicle body and circumferential hat-shaped transverse reinforcement members (12) in the width direction of the vehicle body. The longitudinal reinforcement members (11) and transverse reinforcement members (12) are integrally formed with the outer wall panel skin (15) using a co-curing process. The roof panel (2) and side wall panel (3) are connected longitudinally in the length direction of the vehicle using T-shaped longitudinal reinforcing ribs (50) to connect the longitudinal joints; hat-shaped transverse reinforcing ribs (51) are fitted on the outside of the transverse reinforcing members (12) of the roof panel (2) and side wall panel (3) and connected to form an integral load-bearing frame; in the area connecting the hood (1) and the vehicle body in the circumferential direction, reinforcing strips (53) and transversely set C-shaped circumferential connecting reinforcing frames (52) are fixedly connected, and longitudinal reinforcing ribs at the bottom are processed to make clearance openings. Z-shaped connectors (54) are set on one side plane of the T-shaped longitudinal reinforcing members (11) of the vehicle body and hood and fixed to the vehicle body; in the area connecting the composite material body and the aluminum alloy chassis (5), a continuous carbon fiber composite connecting plate (57) is used to fix the side wall panel (3) of the vehicle body to the aluminum alloy chassis.

2. The integral reinforced composite material vehicle body structure according to claim 1, characterized in that: The transverse reinforcing member (12) is a cap-shaped foam sandwich composite material reinforcing rib. At the position where it intersects with the T-shaped longitudinal reinforcing member (11), the T-shaped reinforcing rib is opened. The height of the cap-shaped reinforcing rib is 20-50mm higher than the maximum height of the T-shaped reinforcing rib section.

3. The integral reinforced composite material vehicle body structure according to claim 2, characterized in that: The opening of the T-shaped reinforcing rib is sealed with an edge-sealing reinforcement layer (13).

4. The integral reinforced composite material vehicle body structure according to claim 1, characterized in that: The longitudinal reinforcing member (11) and the transverse reinforcing member (12) are replaced by a co-bonding process instead of being integrally formed with the outer wall panel skin (15).

5. The integral reinforced composite material vehicle body structure according to claim 1, characterized in that: It also includes an opening reinforcement frame (14) and a reinforcing corner piece (40). An opening reinforcement frame (14) is set in the opening area of ​​the air conditioning vent and window on the roof panel (2) of the vehicle body to reinforce the opening position. The opening reinforcement frame (14) has an L-shaped or C-shaped cross section. The opening reinforcement frame (14) is fixedly connected to the roof panel (2) of the vehicle body by connecting the reinforcing corner piece (40). In the connection area of ​​the opening reinforcement frame (14), the wall panel skin (15) needs to be locally reinforced by using a local reinforcement layer (16).

6. The integral reinforced composite material vehicle body structure according to claim 1, characterized in that: It also includes the side wall and the base frame connecting corner piece (55), which is a triangular reinforcing rib whose shape fits the corner shape of the side wall and the base frame. The side wall and the base frame connecting corner piece (55) connects the transverse reinforcing member (12) of the vehicle body side wall panel to the aluminum alloy base frame.

7. The integral reinforced composite material vehicle body structure according to claim 1, characterized in that: It also includes an integral reinforced door frame (19), a connecting plate (57) and a connecting corner box (56). The integral reinforced door frame (19) is fixedly connected to the longitudinal reinforcing member (11) of the vehicle side wall panel (3) by a Z-shaped connector (54). The integral reinforced door frame (19) is fixedly connected to the transverse reinforcing member (12) by a connecting plate (57). The lower end of the integral reinforced door frame (19) is fixedly connected to the aluminum alloy base frame (5) by a triangular connecting corner box (56).

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